This invention relates to gas operated guns and, in particular, guns capable of firing a projectile, such as a paintball, using pressurized gas.
Guns operated by means of a supply of pressurized gas have been known for quite some time and these guns have been used to fire a variety of projectiles including pellets and small balls. In more recent years, gas operated guns designed specifically to fire paintballs have been developed. The paintballs may comprise a mixture of a liquid including ethylene glycol with the liquid being encased in a fragile gelatin casing and these paintballs are designed to break apart upon striking a target in order to mark same. Paintball guns are now in widespread use for purposes of target practice and mock war games.
A variety of systems and mechanisms are known for operating a paintball gun by means of a trigger. In the semi-automatic gun shown and described in applicant""s U.S. Pat. No. 5,349,939 which issued Sep. 27, 1994, there is a hammer mechanism slidably mounted in the gun, this hammer being biased towards a forwards firing position by a coil spring. There is a sear device mounted on a sear pin and this device is operated by a pivoting trigger. A sear spring biases the sear device so that the front end thereof pivots downwardly after the hammer is released. A small sear detent is slidably mounted in the front end of the sear device and is biased forwardly by a spring. This firing mechanism is relatively complex and requires some skill on the part of the gun assembler to make the gun.
Recently, electronically operated paintball guns have come into use, one such gun being illustrated and described in U.S. Pat. No. 5,967,133 issued Oct. 19, 1999 to Smart Parts Inc. This gun includes three main components, a body which houses all of the pneumatic components and electrical power source, a grip mounted to the body and housing an electrical switch able to activate a launching sequence, and an electrical control unit which directs flow between the pneumatic components. The electrical control unit includes an electrical timing circuit that is activated when an electrical switch is closed. There are two electrically operated valves which are sequentially energized by the timing circuit to enable the loading of a projectile and the release of compressed gas from a storage chamber. Difficulties with guns of this general type include the need for at least one battery that is mounted in the gun and the need for a control circuit and wiring, which can add to the expense of the gun.
It is an object of the present invention to provide a gas operated gun that is relatively inexpensive to manufacture and quite reliable and which does not require the use of a sear mechanism.
It is a further object of the present invention to provide a gas operated gun capable of filing projectiles such as paintballs that employs a relatively simple trigger activated switch mechanism and a so-called pulse valve capable of delivering a pulse of gas to a chamber in the gun in order to drive a hammer to its firing position.
According to one aspect of the invention, a paintball gun includes a gun body, a barrel mounted on the gun body, a trigger movably mounted on the gun body, and a hammer slidably mounted in a chamber formed in this gun body, the hammer being movable between a retracted position and a forward position. The gun includes a first pressurized gas circuit for delivering pressurized propellant gas from a supply to the barrel for propelling paintballs therefrom. This first circuit includes a first valve. The gun further includes a second pressurized gas circuit connectible to a gas supply to receive gas therefrom, this circuit including a pulse valve having a gas inlet and a gas outlet and a trigger-activated switch valve capable of operating the pulse valve and having a valve outlet operably connected to the gas inlet of the pulse valve. The pulse valve is adapted to provide a pulse of pressurized propellant gas at the gas outlet when the trigger is pulled and this gas outlet is operably connected to the chamber for the hammer. During use of the gun, the pulse of propellant gas is capable of driving the hammer to its forward position at which it strikes the first valve to open it and release pressurized propellant gas into the barrel in order to propel a paintball therefrom.
Preferably the gun includes a bolt slidably mounted in a breech of the gun from a retracted position where a paintball can enter the breech to a forward firing position and the hammer is connected to the bolt for movement therewith.
According to a further aspect of the invention, there is provided a gas powered gun for firing balls, this gun being adapted for connection to a source of pressurized gas and having trigger-activated valving for controlling the flow of pressurized gas within the gun. The gun includes a barrel and a breech at a rear end of the barrel for receiving one ball at a time through a ball feed port. A hammer is slidably mounted in a chamber formed in the gun and biased to a retracted, non-firing position. A bolt is slidable within the breech to advance the ball to a firing position and close off the feed port. A first pressurized gas delivery system provides pressurized gas from the source to the barrel for propelling the ball therefrom. This first system includes a gas releasing valve which is opened by the hammer being driven to a firing position. A second pressurized gas delivery system provides a pulse of pressurized gas from the source to the chamber in order to drive the hammer to the firing position. The second pressurized gas system includes a pulse valve which is operated by the trigger activated valving.
According to a further aspect of the invention, a gas operated gun operable to fire projectiles includes a gun body having a gun handle, a barrel mounted on the gun body and a breech connected to a rear end of the barrel. There are a movable trigger mounted on the gun body and a bolt movable in the breech between a rearward position where a projectile can enter the breech through an inlet and a forward firing position. A hammer is connected to the bolt and is mounted for sliding movement in a chamber formed in the gun body between a rearward position and a firing position. A spring is mounted in the gun and biases both the bolt and the hammer towards their rearward positions. A unique aspect of this gun is its pneumatic circuit for operating the hammer, this circuit including a pulse valve and a trigger-activated switch mechanism for operating the pulse valve. The circuit further includes a gas regulator for supplying gas at a predetermined pressure to the pulse valve. The pulse valve has a valve outlet for a pulse of pressurized gas which can be produced by it when the trigger is pulled. This valve outlet is connected by a passage to the chamber for the hammer. A further valve is mounted in the gun body and is adapted to be opened by engagement by the hammer when the hammer moves to the firing position. Opening of this valve permits passage of pressurized gas from a pressurized gas source into the barrel to propel the projectile along and out of the barrel.
Preferably the spring is a coil spring mounted in the breech and engaging the bolt and the switch mechanism is a two-position switch valve mounted in the gun body adjacent the trigger. An outlet of the gas regulator is connected by a gas line to an inlet of the switch valve and an outlet of the switch valve is connected by a further gas line to an inlet of the pulse valve.
Further features and advantages will become apparent from the following detailed description taken in conjunction with the accompanying drawings.